I have done this. Consider the new location- will there be enough room to connect to the drain. Use a sissor tye auto jack to support the disposal during removal and installation. You need to know how the disposal ring releases the disposal from the drain. You will exchange the the sink drains - disposal drain to the new disposal hole - do you know how to putty a drain. The drain connections to the wall will need changes - can you cut and glue ABS drain pipes? If you are reconnecting a dishwasher drain to the disposal, insure it loops to the underside of countertop, and is secured with a clamp. This is not necessary if an air-gap is installed - I prefer to use the lpop and eliminate the air-gap.

The bottom line is this may be beyond the novice ability. Get three estimated from Better Business Bureau (sic) listed companies, choose one and good luck.